Light-duty liquid or gel detergent compositions useful for manual dishwashing operations are well known in the art. Such products are generally formulated to provide a number of widely diverse performance properties and characteristics. First and foremost, liquid or gel dishwashing products must be formulated with enough surfactants and other cleaning adjuvants to provide acceptable solubilization and removal of food soils, especially greasy soils, from dishware being washed in aqueous solutions formed from such products.
In addition to being suitable for cleaning dishes, such compositions will also desirably possess a number of characteristics which enhance the aesthetics of the manual dishwashing operation. Thus, useful hand dishwashing liquids or gels will utilize components which enhance the sudsing performance of the wash solutions formed from such products. Sudsing performance entails both the production of a suitable amount of suds in the wash water initially as well as the formation of suds which last well into the dishwashing process.
Another aesthetics-related feature of suitable manual dishwashing products relates to rinsing performance. Use of highly concentrated or high concentrations of dishwashing products can require an increase in the amount of rinsing that is needed in order to remove detergent composition from the dish article once manual agitation and washing is complete. For example, in direct application conditions, the dish article is dampened and the detergent composition is applied to the dish article in a highly concentrated form or even in its undiluted form. After manual agitation and wiping by the consumer, the article is placed under running water to be rinsed. The article is thus held under the rinsing water until the consumer is satisfied that the remaining detergent material on the dish article has been removed. Completion of rinsing is often evaluated by the complete removal of suds from the dish article and by the lack of a greasy or slippery feel to the dish article to the touch. Under certain consumer washing conditions such as in ambient water conditions and direct application conditions, this problem of achieving complete rinsing is particularly noticeable.
Yet another aesthetics-related feature of suitable manual dishwashing products involves the skin "feel" and skin conditioning benefits which such products can impart to dishwashing solutions made therefrom. With respect to skin "feel", some consumers prefer that the dishwashing solution formed from the product not be slimy or slippery feeling to their hands. Furthermore, acceptable manual dishwashing products should also be mild to the skin, particularly to the hands, and should not cause skin dryness, chapping or roughness. Such skin complaints largely result from the removal of natural oils from the skin during dishwashing. Thus, the manual dishwashing composition should desirably be effective at removing grease from plates but should not serve to remove natural oils from the skin.
Given the foregoing, there is a continuing need to formulate manual dishwashing liquids and gels that provide an acceptable and desirable balance between cleaning performance and product aesthetics. Accordingly, it is an object of the present invention to provide light-duty liquid or gel dishwashing compositions which are especially effective at removing food soils from dirty dishware in the context of a manual dishwashing operation.
It is a further object of the present invention to provide such compositions having suitable and desirable sudsing performance.
It is the further object of this invention to provide such compositions having desirable rinsability characteristics.
It is yet a further object of this invention to provide such compositions which impart a desirable non-slippery skin feel to washing solutions formed therefrom and which provide washing solutions that are desirably mild and non-irritating to the skin.
It has been found that certain selected combinations of surfactants, hydrotropes and skin conditioning enzymes can be made to provide dishwashing compositions which achieve the foregoing objectives. The elements of this selected combination of ingredients are described as follows: